A month or two ago NVIDIA sued Samsung over patent infringement
an now Engadget reports Samsung countersued NVIDIA for infringing on six patents and for misleading consumers with benchmarks that claim the Tegra K1 outpaces the Samsung Exynos 5433:
Samsung definitely isn't taking NVIDIA's first patent lawsuit lying down. The Korean tech firm has countersued NVIDIA not just for allegedly infringing on six patents, but for leading buyers astray with benchmarks for the Shield Tablet. NVIDIA is supposedly trying to "confuse customers" by claiming that the slate's Tegra K1 processor outpaces the Exynos 5433 chip in the Galaxy Note 4; regular benchmarks show that's not true, Samsung claims. The suit also accuses PC vendor Velocity Micro of violating two additional patents (for a total of eight), since NVIDIA's graphics cards play a heavy role in its lineup.
However, as Engadget points out, it seems a case of the pot calling the kettle black as Samsung is known to have done some benchmark inflating of its own.